package com.hmdp.service.impl;

import com.hmdp.dto.Result;
import com.hmdp.entity.SeckillVoucher;
import com.hmdp.entity.VoucherOrder;
import com.hmdp.mapper.VoucherOrderMapper;
import com.hmdp.service.ISeckillVoucherService;
import com.hmdp.service.IVoucherOrderService;
import com.baomidou.mybatisplus.extension.service.impl.ServiceImpl;
import com.hmdp.utils.RedisIdWorker;
import com.hmdp.utils.SimpleRedisLock;
import com.hmdp.utils.UserHolder;
import org.redisson.api.RLock;
import org.redisson.api.RedissonClient;
import org.springframework.aop.framework.AopContext;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.data.redis.core.StringRedisTemplate;
import org.springframework.stereotype.Service;
import org.springframework.transaction.annotation.Transactional;

import javax.annotation.Resource;
import java.time.LocalDateTime;
import java.util.concurrent.TimeUnit;

/**
 * <p>
 * 服务实现类
 * </p>
 *
 * @author 虎哥
 * @since 2021-12-22
 */
@Service
public class VoucherOrderServiceImpl extends ServiceImpl<VoucherOrderMapper, VoucherOrder> implements IVoucherOrderService {

    @Resource
    private ISeckillVoucherService seckillVoucherService;

    @Resource
    private RedisIdWorker redisIdWorker;

    @Autowired
    private StringRedisTemplate stringRedisTemplate;

    @Autowired
    private RedissonClient redissonClient;

    @Override
    public Result seckillVoucher(Long voucherId) {
        //1.查询优惠券
        SeckillVoucher voucher = seckillVoucherService.getById(voucherId);
        //2.判断秒杀是否开始
        if (voucher.getBeginTime().isAfter(LocalDateTime.now())) {
            return Result.fail("秒杀还未开始!");
        }
        //3.是否结束

        if (voucher.getEndTime().isBefore(LocalDateTime.now())) {
            return Result.fail("秒杀已经结束");
        }

        //4.判断库存是否充足
        if (voucher.getStock() < 1) {
            return Result.fail("库存不足");
        }
        //用户id
        Long userId = UserHolder.getUser().getId();

        //创建锁对象
//        SimpleRedisLock lock = new SimpleRedisLock("order:" + userId, this.stringRedisTemplate);
        RLock lock = redissonClient.getLock("lock:order:" + userId);
        //获取锁
        boolean isLock = lock.tryLock();

        if (!isLock) {
            //获取锁失败
            return Result.fail("一个人只能下一单");
        }
        try {
            //获取代理对象
            IVoucherOrderService proxy = (IVoucherOrderService) AopContext.currentProxy();
            return proxy.createVoucherOrder(voucherId, userId);
        } finally {
            lock.unlock();
        }


    }

    @Transactional
    public Result createVoucherOrder(Long voucherId, Long userId) {
        //一人一单


        int count = this.query().eq("user_id", userId)
                .eq("voucher_id", voucherId)
                .count();
        if (count > 0) {
            // 用户已经下单
            return Result.fail("用户已经购买过一次了");
        }
        //5.扣减库存
        boolean success = seckillVoucherService.update()
                .setSql("stock = stock-1")
                .eq("voucher_id", voucherId)
                .gt("stock", 0)//where id= #{id} and stock >0
                .update();
        if (!success) {
            return Result.fail("库存不足");
        }


        //6.创建订单
        VoucherOrder voucherOrder = new VoucherOrder();
        //订单id
        long orderId = redisIdWorker.nextId("order");
        voucherOrder.setId(orderId);

        voucherOrder.setUserId(userId);
        //代金券id
        voucherOrder.setVoucherId(voucherId);

        this.save(voucherOrder);
        //7.返回
        return Result.ok(voucherOrder);

    }
}
